The present application is a divisional of U.S. patent application Ser. No. 15/423,287, filed Feb. 2, 2017, now U.S. Pat. No. 10,125,439, the disclosure of which is herein specifically incorporated in its entirety by this reference.
Fireproof curtains or partitions are often used in civil construction settings between rooms and adjacent elevators. Fire curtains do not contain windows, which makes determining whether hazardous conditions exist behind the fire curtain difficult for firefighters. Currently, materials developed for fire and smoke curtains which provide both smoke and flame penetration resistance are not translucent or transparent.
Conventional materials used in fire curtains do not achieve the combination of a desired transmissivity of light, while meeting regulatory requirements in terms of flammability resistance. As such, conventional fire curtains are opaque. In fire and smoke curtain applications, materials such as polyamide and silicone films have been used to eliminate smoke penetration but do not provide adequate protection from flame penetration. Therefore, it is highly desirable that fire curtains have translucent or transparent composite panels comprised of translucent or transparent composite materials that offer protection from high temperature fires.
Existing translucent or transparent composite materials can offer protection from high temperature fires (see U.S. Pat. No. 5,552,466 and U.S. Patent App. Pub. No. 20100093242). However, due to their rigidity and other undesirable properties, these composite materials have not been utilized in fire curtains. Methods for manufacturing rigid translucent or transparent composite materials, which are used in application such as surfboard manufacturing, include combining an opaque, fine fiberglass fabric with a refractory index controlled acrylic resin that matches the refractory index (RI), or refractory index value, of the fiberglass substrate.
For a translucent or transparent composite material to be viable for use in fire curtains, it is necessary that it be flexible. It is also desirable that a flexible, translucent or transparent material be low-cost in terms of manufacture and raw material costs. A translucent or transparent composite panel in a fire curtain must allow transmission of enough visible light to ascertain conditions behind the curtain.
Accordingly, there is a need in the art for a translucent or transparent, flexible fire curtain composite panel which can prevent flame and smoke penetration.